1. Field of the Invention
This invention relates to vacuum cleaner hose manufacture, and in particular to the manufacture of a hose end for use with press-on terminals utilizing sharp wedging means for effecting the desired electrical connection of the terminals to the hose conductors or wires.
2. Description of the Background Art
A vacuum cleaner hose and structure is presently in public use in the vacuum cleaner manufacture industry wherein a hose end connector or cuff is molded about a pair of terminals wedged onto the ends of a pair of helically extending electrical conductors included in the hose carcass. Such construction has been found to sometimes result in an inaccurately spaced disposition of the terminals and inaccurate disposition thereof relative to the longitudinal axis of the hose for a number of reasons. It has been found that it is difficult to maintain the alignment of the terminals because of the springy nature of the electrical conductors which advantageously may be fabricated using copper coated spring steel wire and which serve both as means for conducting the electrical current through the hose and spring reinforcing means of the hose carcass. Thus, while the terminals may be temporarily retained in the desired disposition in the mold by suitable mold formation, such springiness has been found to cause undesirable movement of the terminals upon removal of the newly formed hose end from the mold as the molding material, at this stage in the manufacture, it is relatively soft and yielding.
As the terminals must be accurately located for proper fit with a complementary terminal structure in connecting the hose and electrically to a complementary fitting, such misalignment of the terminals may present a serious problem.
One solution to this problem is to retain the molded hose end in the mold for a sufficiently long time to permit substantial rigidification of the molded material before removal therefrom. Such a solution has the serious disadvantage of substantially increasing cost because of the reduction in rate of manufacture.
The mechanical connection of the terminals to the hose conductors causes the terminals to be supported in part by the hose conductors which, as discussed above, may cause the terminals to have an undesirable skewed relationship with each other and with the hose axis. Where the hose end is molded about such terminals without providing any further support thereto, the hose end may be inoperative for the purposes intended, thus causing a relatively high scrap rate in the manufacturing process. Where the terminals are maintained temporarily in the desired aligned disposition during the molding operation, they may temporarily be properly aligned but become misaligned as a result of the forces acting thereon developed by the springiness of the hose wires.
The concept of utilizing the molded hose end for providing the sole support (excepting the support provided by the hose conductors) for the electrical connectors is disclosed in Wickham et al U.S. Pat. No. 3,636,285 which further teaches that the electrical devices which are embedded in the hose connector plastic may be male or female connectors as well as electrical switches.
In U.S. Pat. No. 2,516,862, A. W. Gilmore et al show a method of making a vacuum cleaner hose wherein a female electrical connector is provided in a molded-on sleeve at the end of the hose carcass.
In U.S. Pat. No. 3,127,227 of Charles E. Edwards, the hose connector consists of inner and outer sleeves formed of plastic material for jointly locking the electrical fitting in place at the end of the hose carcass.
Lincoln I. Opper, In U.S. Pat. No. 3,314,039, shows a vacuum cleaner hose connection wherein a pair of terminals are embedded in a plastic collar which serves as the sole support for the terminals. The collar is slid over the projecting portion of an inner sleeve into abutment with a shoulder on the sleeve with hollow wire ends on the collar sliding into electrical connection with the ends of the wire of the hose carcass.
Charles J. Pauler et al, in U.S. Pat. No. 3,034,085, which patent is owned by the assignee hereof, show a vacuum cleaner hose construction wherein the terminals are retained by a collar.
The concept of utilizing sharp edge wedge-type terminal connections which slice through to the conductor wires is shown in U.S. Pat. No. 3,683,319 of George H. Vigeant et al.
Another patent showing the use of a sharp edge notch-type connector is that of William S. Sedlacek, U.S. Pat. No. 3,848,954, which teaches the use of a notch having relatively sharp corner edges preceding the slot so as to permit cutting of the insulation as the wire is brought downwardly into the slot.